Ingestion of ethanol by pregnant women or laboratory animals produces fetal damage. Animal studies indicate that ethanol increases fetal deaths if given to the father prior to mating. It is proposed that the mechanism of this effect is a derangement by ethanol of the intricate pattern of endocrine events required for the production of normal sperm. Changes in luteinizing hormone (LH) and testosterone (T) are known to occur after acute and chronic ethanol use but they have been incompletely characterized. The proposed study will use sophisticated techniques including specific RIA for follicle stimulating hormone (FSH), LH and T and a non-stressful frequent sampling method to determine the effect of a single injection of ethanol on the patterns of secretion of these hormones. A unique feature will be the use of the recently synthesized hypothalamic peptide LH-RH to determine whether ethanol alters the pituitary response to its hypothalamic stimuli. Purified LH will be infused to discriminate between a pituitary or a hypothalamic site of action for ethanol suppression of T release. These experiments will establish how ethanol alters the rhythmic secretion of LH, FSH and T and whether it acts at the hypothalamus, the pituitary, the testes or a combination. Future studies under consideration would be to determine the effects of longer ethanol treatment and to relate changes in FSH, LH and T to abnormal sperm or semen production.